No model



v PATENTBD JAN. 12, 1904.

D. J. MARES.

KILN.

APPLICATION FILED MAR. 11,*1903.

2 SHEETS-SHEET l.

N0 IODEL.

NS@ N.

No. 749,208. PATBNTBD JAN. 12, 1904. D. J. MARES.

KILN.

- y 'APPLIGATION FILED MAB. 11. 190s. No MoDBL. v 2 SHEETS-SHEET 2.

Tu: Nonlus PETERS cu. mmmuvnm wAswuow-n n ci Patented January i2, 1904.

PATENT OFFICE.

DAVID JASPER MARRS, OF DENVER, MISSOURI.

SPECIFICATION forming p art of Letters Patent No. 749,208, dated January12, 1904.

Application filed March 1l, 1903.

To a/ZZ whom it may concern.-

Beit known that I, DAVID JASPER MARRs, a citizen of the United States,residing at Denver, in the county of Worth and State of Missouri, haveinvented a new and useful Kiln, of which the following is aspecification.

My invention relates to kilns for burning brick or tile, and moreespecially to that type ofkilns known as open-top downdraft-kilns.

The objects contemplatedr by my invention are, first, to secure economyof fuel, and, second, to so control the temperature in the va riousparts of the kiln that all the bricks or tiles may be burned toasuflicient degree kof hardness and make the number of bricks or tilesruined by excessive heat as smallas possible. I attain these results byconstructing a kiln and arranging the charge of brick or tile thereinafter the manner hereinafter fully described, and shown in theaccompanying drawings, of which- Figure 1 is a longitudinal sectionbroken through in the middle in order 'to make the figure of convenientsize. Fig. 2 is a ground 'plan broken through in similar manner. Fig. 3is a vertical transverse section, and Fig. 4 is a detail view showingthe arrangement of one of the fire-pots in the upper portion of thecharge of brick. Y Y

In Figs. 1 and 3 the number ofcourses of brick shown in the kiln is muchsmaller than would be employed in practice. This discrepancy isunavoidable on account of the necessarily small size of the drawings, asany attempt to show the actual number of courses would make the scaletoo small for reproduction.

In all the above-mentioned figures correspending parts are indicated bysimilar char acters of reference throughout.

Referring to the drawings, 1 represents the front end wall of a kilnconstructed according to my invention, 2 the `rear end wall, and 3 3 theside walls.

4 4 4, &c., are fire-boxes arranged side by side in the front wall ofthe kiln, each iireb ox being provided with an ash-pit and door, asusual. I

5 is the iioor of the kiln, and 6 6 are iiues arranged one on eitherside of the kiln and Serial No. 147,340. (No model.)

below the level of its floor. At their forward ends the iues 6 6 areclosed by end walls 7 7, which, it will be observed, are some distancein front of the hre-boxes 4 4, &c. Ordinarily I place the-front endwalls of the flues about fifteen feet beyond the inner ends of thefiremay be of any preferred form but that shown in the drawings andconsisting merely of a sliding` plate movable in suitable guideways isone which I have found entirely satisfactory. Beyond the rear wall ofthe kiln the ues 6 6 turn toward the median line of the kiln and openinto a single stack 11.

The bricks should be arranged in the kiln three over three or Eve overfive, the former being the arrangement shown inthe drawings, andlongitudinal arches 12 12 12 from four to six bricks in height should bemade along the bottom of the charge. It will be observed that there is alongitudinal arch for each fire-box, and consequently these arches serveto form a part of the draft system. Transverse arches 13 13 13, vctc.,are also arranged in the botton of the charge of brick or tile, eachtransverse'arch being of about the same dimensions in height and breadthas the-longitudinal arches above mentioned and being so placed that eacharch connects correspondingly-placed dampers in the side fines 6 6.

In the top of the charge of brick I provide transverse rows of fire-pots14 14 14, &c., extending downward to a depth of about eight or teninches, approximately, the transverse rows being about three feetapartand the firepots in each row being separated by about the sameamount of space. Each fire-pot is pro-I vided with a closure-plate 15,by means of which the downward draft through the firepots may be shutofi whenever desired, and in order tov prevent the escape upward oftheIOO hot air-currents from the fire-boxes the charge of brick isprotected by a four-inch layer of earth spread over two courses of bricklaid broadside down. The firing-pots are placed at the top of openingsextending downward through the charge of brick and communicating withthe cross-arches at the bottom thereof, thus forming channels throughwhich coal in the form of slack may be deposited on the bottom of thekiln.

In burning brick or tile in a kiln constructed according to my inventionfires are rst started in the fire-boxes at the end of the kiln andallowed to burn slowly in order to watersmoke the kiln before beginningthe burning process proper. In carrying out the water-smoking of thekiln all of the dampers in the side fiues 6 6 are closed at first exceptthose nearest the front of the kiln, which are left open to cause adraft through the front section of the kiln. After the front section ofthe kiln has become heated to the desired temperature the front dampersare closed, and the next set of dampers is opened and kept open untilthe next section of the kiln is watersmoked, when they are closed andthe set of dampers next in advance is opened to watersmoke that section.This mode of procedure is continued until the entire kiln has beenwatersmoked. The burning proper is carried on in much the same way asthe water-smoking, except thatin theburning or firing process use ismade of the fire-pots in the top of the charge of brick for introducingfine coal in order to burn all of the brick except that nearest to thefire-boxes at the front of the kiln. In firing, as in water-smoking, theprocess is begun at the front of the kiln by increasing the heat of thefires used in water-smoking until the temperature is high enough toraise the brick in the first twenty or thirty feet of the kiln to a redheat. Then the doors of the fireboxes are closed and fine coal or slackis introduced through the first row of fire-pots in the top of the kiln.The slack introduced through these fire-pots passes downward toward thebottom of the kiln; but a considerable portion of the slack lodges uponthe irregular surface presented by the brick surrounding the openingleading from the firepot to the bottom of the kiln. The temperature ofthe brick at the time the fine coal is introduced'is such that it is seton fire merely by contact therewith, and the heat developed from theburning of .the slack is sufficient to raise the temperature oftheadjacent section of the kiln to the point necessary to ignite slackwhen introduced through the next row of fire-pots. The management of thedampers in the firing process is substantially the same as in thewater-smoking process. When the front section of the charge of brick inthe kiln is being burned by means of the heat obtained from thefire-boxes, the first set of dampers in the fiues 6 6 will be kept open,and

when the doors ofthe fire-boxes are closed and the burning of the nextsection of brick is carried on by means of fine coal introduced throughthe fire-pots at the top of the kiln that set of dampers will be closedand the next set will be kept open. This procedure is continued inburning the entire kiln; but in order to furnish draft in burning thesections more remote from the front of the kiln the doors in thefire-boxes are opened and air is allowed to enter and pass through thesection of brick at, the forward end, which has already been burned.This air from the outside of the kiln serves to cool off gradually theburned sections at the front of the kiln and also to produce draftthrough the sections which are in process of being burned.

It will be readily seen that in burning brick in a kiln such as I havedescribed and proceed ing as I have explained the heat is generatedpractically all through the kiln, as required, instead of being producedin substantially one portion and transmitted by fiues from this portionthrough the remainder.' The advanvtage resulting from this arrangementis obvious. In order to burn all the brick thoroughly by means of afurnace at one end of the kiln, it would evidently be necessary to havean extremely high degree of heat in the furnace in order to insure asufiiciently high temperature at the end of the kiln most remotetherefrom. Such high temperature in the furnace is undesirable, for thereason that the waste of heat increases in proportion, roughly speaking,to the increase in tempel'- ature of the furnace and, further, becausethe bricks nearest the furnace and subjected to excessive heat would beto a certain extent fused together and rendered unfit for use. A furtheradvantage is obtained by constructing the kiln and arranging the chargeof brick in the manner described-that is, by having a larger number ofsmall fire-pots in the top of the charge of brick and using a small firein each I am enabled to use for most of the burning slack coal, which isthe cheapest form of fuel obtainable.

Having now fully described and shown the construction of my inventionand explained the mode of operation thereof, what I claim as new, anddesire to secure by Letters Patent, is

1. In a brick-kiln, a permanent floor, side and end walls, a furnace atone end comprising a plurality of sections, a smoke-stack at the otherend, fiues beneath said floor extending from a point at a distance fromsaid furnace to said stack, dampers in said floor communicating withsaid fiues, a body of green brick inclosed by said walls, longitudinalpassages in the body of said green brick communicating with the sectionsof said furnace, transverse passages in said body of green brickextending between corresponding dampers, fire-pots in the top of saidbody of green brick,

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passages leading from said lire-pots to the transverse passagesextending across said body of green brick, and means for operating saiddampers.

2. In a brick-kiln, a permanent floor, side and end walls, a furnace atone end, a smokestack at the other end, flues beneath said oor and atthe sides thereof, said iiues extending from a point at a distance fromsaid furnace to said stack, dampers in said floor communieating withsaid iiues at intervals throughout their length, afbody of green brickinclosed by said walls, longitudinal passages in said body of greenbrick communicating with said furnace, transverse passages in said bodyof green brick extending between correspondingly-placed dampers,fire-pots in the top of saidpbody of green brick, passages extendingdownward from said fire-pots to said transverse passages, and means foroperating said dampers.

In testimony that I claim the foregoing as my own I have hereto aiiixedmy signature in the presence of two witnesses.

DAVID "J ASPER MARRS.

Witnesses:

E. MILLER, A. J. MANNING.

